Backwater valve



i 5,1927 D. FoRFAR BACKWATER VALVE Filed Aug. 15, 1925 2 Sheets-Sheet 1j 1,62 ,586 Apnl 5,1927. DFQRFAR 3.

BACKWATER VALVE Filed Aug. 15, 1925 2 Shgets-Sheet 2 Patented Apr.-$31927.

] UNITE s'rAr s 1,623,586 Ares-r ossics.

' 1301mm; scares. or rvirnnnnronrs, MINNESOTA; I

BAGKWATER V LVE.

Application filed'August 15, 1925.' Serial No. 50,372.

to close the backwatervalve, and again autos.

inatically setin motion by the receding of said water to open said valveT his mechanism when once set in n iotion to. either open or close thebackwater valve'is operated by a inotive power entirely independent ofthe flood water in the sewer connection.

Preferably, as. illustrated, water under pressure is'tal-zen trout. itymains or any other available source of water supply under pressure andis used to hydraulically operate the backwater valve. p

To the above end generally stated, the in.- ventien cons sts ofrhe noveldevices and combinations of devices hereinaitter deseribed and defined nthe claims. a

In the accompanying drawings, which illustrate the invention; likecharacters indicate like parts throughout the several views. i

lleterr in Fi 1 is. ion'partly side elevation ant. partly in eilliffilfllel'ilcdl section; 1

2 and 3 are views t motor valves principally in central verticalsection; i Fig. 4 is elevation (its three-way valve and connections foroperating the same, some parts beingshownin different positions by meansof" broken lines;- and .Fig. 5 is a view of the tl'iree-way valve incentral vertical section.

The. nuinoralii indicates a sewer pipe the 'no-rn ial direction of flowtherein beingindicated by the arrow on 1. interposed in the sewer pipe 6is'a valve casing? in whieh'is mounted a quick opening pattern gatevelvet; having an upright valve stem 9 working through stuifingbox onthe top of said casing and during normal conditions said valve is open.To the upper end of the valve stem. 9- is securedan extension thataffords a piston rod 10 having secured there to apps-rand lowerditlerential pistons 11 and 12 respectivelyyt i 'loriner of which has aniuoh greater areathanthelatter. These g to the drawings:

fragmentary iew of the invenpistons 11 and 12 work in co -operatingcylinders 13 and 14, respectively, andthe' piston rodlO works throughstufiing boxes on the lower head of the cylinder 13' and on both headsof the cylinder 14.

Interposed in the sewer pipe 6 outward of. the valvecasing- 7, inrespect to the discharge from said pipe, is a pipe fittinghaving anupstanding cylindrical casing 15 for a float chamber 1G in which ismounted a float 17 secured to the intermediate portion or a float stem.18 The lower portion of the float stem 18 is mounted in a spider' 19secured tothe casing 15 below the float 17', and

the upper end of said stein Works through a Stu-fling box in the top ofsaid casing." A sediment screen 22 issecured to the spider 19, andseparates the heat chamber proper from the sewer pipe 6,

The numerals 2'3 and 2a indioate'inotor valves identical the one withthe other. The motor valve 23 includes a cylindrical up-. right casing25 within which is a water sup.- ply chamber 26 connected atthe bottom awater supply pipe 27 leading from any suitable source of water supplyunder pressure, such as a eitywater supply system. The upper end of thecasing 25 is open and affords a valve seat casing 25 is a waterdischargechan1ber the casing 30 of which atit's bottom is tegrally formed withthe lower end of the. casing 25, and at its top is open and extendssomewhat above thevalve seat 28. A doniee like cover 81 for the casing30 1s bolted or 28. Surrounding the otherwise detachably secured to thetop.

thereof and within which is a water 3 sure chamber32. "Awater supplypipe leads from the water discha-rgc chamber to the cylinder 13. atthetop thereof. A

relatively small branch water supply pipe as. leads from the watersupplypipe 2?:0 the cylinder 14 at the bottom thereof.

A differential valve 35 is mounted on the valve seat 28' for opening andclosing the i l? ter supply chamber 26 to the Water dis: charge chamber29 and for closing said two chambers to the water pressure chains her32. The small area of thisditlere r. tial valve 85 is in thewater supply.Chlilfik her 26 and the large area thereof is in the water pressurechamber 32. A pliable packingBG, secured in a peripheral groove in thedifferential valve35, is arranged to rest on the valve seat 28 when'saidvalve is closed to form a water-tight joint between the chambers 26 and29. The differential valve 35 is carried by a diaphragm 37 formed as apart of the packing 36 and secured in position by having its outermarginal edge portion clamped between the top of the casing and thecover 31. A constantly open axial port 38 extends completely through thedil i'erential valve and connects the water supply chamber 26 to thewater pressure chamber 32. Intcgrally formed with the small area 01 thedifferential valve is a depending hollow stem 39 that extends looselyinto the casing 25 for guiding said valve. Formed in the stem 39 at itsupper end is a plurality of circumt'erentially spaced ports 40 for thepassage of water through said hollow stem from the water supply chamber26 to the water discharge chamber 29 when the differential valve 35 isopen. During normal conditions, the differeutial valve 35 is closed, asshown in Fig. 2.

As previously stated, the motor valve 24 is identical with the motorvalve 23 and includes a cylindrical upright casing 41 within which is awater supply chamber 42, and a water supply pipe 43 for said chamberleads from the water supply pipe 33 to the bottom of said chamber. Theupper end of the casing 41 affords a valve seat 44. Surrounding thecasing 41 is a water discharge chamber 45, the casing 46 of which, atits bottom, is integrally formed with the lower end of the casing 41 andat its top is open and extends somewhat above the valve seat 44. Adome-like cover 47 for the casing 46 is bolted or otherwise detachablysecured to the top thereof and within said cover is a water pressurechamber 48. A waste water pipe 49 leads from the water discharge chamberto the float chamber 16 at the top thereof.

A differential valve 50 is mounted on the valve seat 44 for opening andclosing the water supply chamber 42 to the water discharge chamber 45and for closing said two chambers to the water pressure chamber 48. Thesmall area of the differential valve 50 is in the water supply chamber42 and the large area thereof is in the water pressure chamber 48. Apliable packing 51, secured ina peripheral groove in the differentialvalve 50, is arranged to reston the valve seat 44 when said valve isclosed to term a water-tight joint between the chambers 42 and 45. Thedifferential valve 50 is carried by a diaphragm 52 formed as a part of?the packing 51 and secured in position by having its outer marginal edgeportion clamped between the top of the casing 46 and the cover 47. Aconstantly open axial port 53 extends completely through thedifferential valve 50 and connects the water supply chamber 42 to thewater pressure chamber 48. Integrally formed with the small area of thedifi'erential valve 50 is a depending hol low stem 54 that extendsloosely into the casing 41 for guiding said valve. Formed in the stem 54at its upper end is a plurality of circumferentially spaced ports 54 forthe passage of water through said hollow stem from the water supplychan'iher 4-2 to the water discharge chamber 45 when the differentialvalve 50 is open. Under normal conditions the differential valve 50 isopen, as shown in Fig. 3.

For automatically controlling the motor valves 23 and 24 I provide athree'way rotary valve 55 mounted in a cylindrical casing 56. from thewater pressure chambers 32 and 48, respectively, to the three-way valveA small waste water pipe 59 leads from the three-way valve 55 to thefloat chamber 16 at the top thereof. These water pipes 57 and 58 and thewaste pipe 59 open into the valve casing 56 at circumtereutially spacedpoints, forty-live degrees apart. A radial arm 60 is secured to theshaft (31 of the three-way valve 55 for operating the same. and whicharm is connected to the upper end of the float stem 18 by a slot and pinconnection 62. The three-way valve 55 has three radial ports (33, 64 and65, which communicate the one with the other, and during normalconditions said valve closes the water pipe 57 and connects the waterpipe 58 to the waste water pi e 59 through the ports 63 and 65.

Under normal conditions, the float 17 is in its low position and holdsthe three-way valve 55 in a position to close the water pipe 57 andconnect the water pipe 58 to the waste water pipe 59 through the ports63 and 65, as shown in Fig. 5. As previously stated, the water pipe 57is closed by the three-way valve and a water pressure has been built upin the water pressure chamber 32 through the port 38 from the watersupply pipe 27, and which built-up pressure, acting on the large area ofthe ditferent-ial valve 35, holds the same closed and, hence, cuts offthe water supply to the large piston 11 through the water pipe 33. lViththe water supply pipe 27 closed at the motor valve 23, the waterpressure in the cylinder 14, which is connected by the pipe 3-1 to thewater supply pipe 27, holds the piston 12 raised which in turn holds thegate valve 8 open, as indicated in Fig. 1. to permit a free flow throughthe sewer pipe (5 in the direction of the arrow on said figure. lVhenthe gate valve 8 is open, the piston 11 is in its high position and thecylinder 13 is open for drainage to the sewer pipe 6 through the pipes33 and 43. motor valve 24. pipe 49 and float chamber 16.

As the water supply pipe 27 is closed by the motor valve 23, the watersupply to the motor valve 24 is cut off and, hence, the

Small water pipes 57 and 58 lead loo ill

same is open, as shown in Fig. 3. The Water pressure chamber 48 in themotor. valve float 17 Will he moved thereby into its high position, asindicated by broken lines in Fig. 1, thereby automatically operating thethreeway valve 55 to closethe water pipe 58 and connect the Water pipeto the waste pipe 59 throughthe ports 63and -64. By connecting. thewater pipe 57 to the aste pipe 59 through the threeavvay valve 55, thebuilt-up Water pressure in the pressure chamber 3Q'Wlll be released andthe Water pressure in the pipe27, acting on the small area of thedifferential valve 35, Willopen said valve and cause a flow fromthewa'ter supply chamber 26 into the Water CliSChargc chamber 29 andfrom thence into the cylin der. 13 through the pipe During this sametime, Water entering the pipe 43 from the Water supply pipe 27 throughthe open motor valve 24 and Water pipe 33 will till the atersupplychamber 42 and start building up a ater pressure in the water pressure chamber 48th1ough the port 53, due to the fact that the water pipe58isclosed by the threeay valve 55. When sufficient vvater pressure isbnilt up in the pressure chamber 48 on the. large area of thedifferential valve, 50 to overcome the water pressure on the m ll ar areof, Sa d va e w ll. be. closed against the ater pressure from thewater supply pipe At thetiine the differential valve 50is closed thepnessureof Water. released to the cylinder 13 from the Water supply pipe27 by the openingof the.

motor valve 23Wlll-1I1QVQ the large piston 11 down byO.V$1CO1111I1g-tll8 itter pressure the cylinder 14 on the small piston12 V operate the valvev .8 and close the sev er pipe 6,, as indicated bybroken lines in P 1,. to stop, further. inflow of flood water and holdsaid gate valve closed longas the flood water holds the floatql'Zraised.

hen the flood water in the sewer pipe 6 has receded, the float 17 willreturnto normal position, thereby automat cally operating the three-Wayvalve to close Water pipe 57 to. the Waste Water pipe and open the Waterpipe 58,300, said Waste pipe. lVith the closing of thepip e .57 to theWaste p pe 59 and the opening of the pipe 58 thereto 5 by thetln'ee-ivay valve 5.5, water pressure Will start to build up in theWater pressure chamber 32 throughthe, port 33 and again close thedifferential valve and, hence, close the Water. supply from the pipe 27to the cylinder 13, At the same time, the water pressure in the motorvalve 24 will be released through the pipe 58,, ports 63 and 65. tothefloat chamber 16 and the ivater in the ater dischargechamher 4.5.will Waste through the pipe 49 to said, float chamber and thereby all-0Wthe ditlerentialvalve 50 to open. By the closing of the n otorvalve 23,the Water supply to the cylinder 13 is cut off and theopening of themotor valve 24 permits said cylinder to be. drainedto the float chamber16 through the pipes 33 and 43, motor valve 24 and pipe 49 during theraising of the. large piston 11 under the action of the Water pressureon the small piston 12. By the raising of the small piston 12 the gatevalve 8, is lifted and thereby opens theseWer pipe 6 for normalconditions. Leading from the top of the float chamber 16 is a vent pipe66 Whatl claim is: I I

1..Ina pipe line, the combination with a normally open gate valve forclosing the pipe line, of a main water pipe leadingtrom a source ofsupply under pressure, main and supplemental differential, cylinders andpistons for opening and closing the gate valve,

niain piston having. a much largerarca than the supplemental piston,said two cylinders lacing connected to the main Water pipe, the Waterpressure in the supplement-a cylinder being-constant and normally hold-jing the supplemental piston with thegate valve open, said main cylinderhaving Waste pipe, valves adapted tov be closedby the Water pressure inthe main water pipe and normally closing the water supply to the maincylinder and opening the. VeSie pipe therefrom, and automatic means for;

alternately releasing the ater pressure in said valves to. permitthesame to open.

, v C gate valve, saidmam p ston having amuch stone i ll) larger areathan the supplementalpiston, main and supplemental inotorvalvcs interposed in the main Water pipe, the latter in advance of the. former, thesupplemental cylinder being connected to the main ivate pipe in advanceof the main motor valvey said main cylinder being connected tothe mainWater pipev between the tvvo motor valves, said main motor valvenormally closing the main ater pipe to the supplemental motor valve andthe main cylinder, said main Water pipe being connected to the twocylinders on opposite ends of their pistons, the Water pressure in thesupplemental, cylinder normally holding the supplemental piston With thegate valve open and automatic means for. alternately opening and 1closing the motor valves.

4. The structure defined in claim 3 in further combination with a drainpipe leading from the supplemental motor valve for draining the maincylinder during the opening of the gate valve.

The structure defined in claim 3 in which said automatic means includesa three-way valve.

6. In apipe line, the combination with a normally open gate valve forclosing said pipe line, of a main water pipe leading from a source ofsupply under pressure, main and supplemental difierential pistons andcylinders for opening and closing the gate valve, said main pistonhaving a much larger area than the supplemental piston. main andsupplemental motor valves interposed in the main water pipe, the latterin advance of the former, the supplemental cylinder being connected tothe main water pipe in advance of the main motor valve, said maincylinder being connected to the main water pipe between the two motorvalves, said main motor valve normally closing the main water pipe tothe supplemental motor valve and the main cylinder, said main water pipebeing connected to the two cylinders on opposite ends of their pistons,the water pressure in the supplemental cylinder normally holding thesupplemental piston with the gate valve open, each of said motor valveshaving a differential valve and a pressure chamber in which waterlaressure may be built up from the main water pipe to close said valve,a three-way valve having a drain pipe, a pipe connection from thepressure chamber of each motor valve to the threeway valve, andautomatic means for operating the three-way valve to alternately openand close the pipes from the pressure chambers to the waste pipe of thethree-way valve.

7. In a pipe line, the combination with a normally open gate valve forclosing said pipe line, of a main water pipe leading from a source ofsupply under pressure, main and supplemental differential pistons andcylinders for opening and closing the gate valve, said main pistonhaving a much larger area than the supplemental piston, main andsupplemental motor valves interposed in the main water pipe, the latterin advance of the former, the supplemental cylinder being connected tothe main water pipe in advance of the main motor valve, said maincylinder being connected to the main water pipe between the two motorvalves, said main motor valve normally closing the main water pipe tothe supplemental motor valve and the main cylinder, said main water pipebeing connected to the two cylinders on opposite ends of their pistons,the water pressure in the supplei'nental cylinder normally holding thesupplemental piston with the gate valve open, each of said motor valveshaving a differential valve and a pressure chamber in which waterpressure may be built up from the main water pipe to close said valve, athree-way valve having a drain pipe, a pipe connection from the pressurechamber of each motor 'alve to the three-way valve, and automatic meansin the pipe line adapted to be actuated by liquid in the pipe line foroperating the three-way valve to alternately open and close the pipesfrom the pressure chambers to the waste pipe or" the three-way valve.

8. In a pipe line, the combination with a normally open gate valve forclosing said pipe line, of a main water pipe leading from a source ofsupply under pressure; main and supplemental dilferential pistons andcylinders for opening and closing the gate valve, said main pistonhaving a much larger area than the supplemental piston, main andsupplemental motor valves interposed in the main water pipe, the latterin advance of the former, the supplemental cylinder being connected tothe main water pipe in advance of the main motor "alve, said maincylinder being connected to the main water pipe between the two motorvalves, said main motor valve normally closing the main water pipe tothe supplemental motor valve and ti e main cylinder, said main waterpipe being connected to the two cylinders on opposite ends of theirpistons, the water pressure in the supplemental cylinder normallyholding the supplemental piston with the gate valve open, each of saidmotor valves having a differential valve and a pressure chamber in whichwater pressure may be built up from the main water pipe to close saidvalve, a three-way valve having a drain pipe, a pipe connection from thepressure chamber of each motor valve to the three-way valve, and a floatin the pipe line for operating the three-way valve to alternately openand close the pipes from the pressure chambers to the waste pipe of thethree-way valve.

9. In a pipe line, the combination with a normally open gate valve forclosing said pipe line, of a main water pipe leading from a source ofsupply under pressure, main and supplemental differential pistons andcylinders for opening and closing the gate valve, said main pistonhaving a much larger area than the supplemental piston, main andsupplemental motor valves interposed in the main water pipe, the latterin advance of the former, the supplemental cylinder being connected tothe main water pipe in advance of the main motor valve, said maincylinder being connected to the main water pipe between the two motorvalves, said main motor valve normally closing the main water pipe tothe supplemental motor valve and the main cylinder, said main water pipebeing connected to the two cylinders on opposite ends of their pistons,the water pressure from the main Water pipe to close said valve, athree-Way valve having a drain p1pe,a

pipe connection'from the pressure chamber 7 of each motor valve to thethreewa valve a float chamber in the pipe line, and a float inthe floatchamber for'operating the threefway valve to alternately open and closethe pipes from the pressurechambers to the Waste pipe of the three-Wayvalve. 7

10. The structure defined in claim 9 in which the Waste pipes from thesupplemental motor valve and the three-Way valve are arranged todischarge into the float chamber. 11. The structure defined in claim 31n which each of the motor valves has a differentialvalve embodied in adiaphragm, a pressure chamber With 7 a constantly open port andin whichWater pressure from the main Water pipe may be built up to close saidvalve and automatic means'including a valve for alternately opening andclosing said pressure chambers. V

12. The structure defined in claim 9 in further combination with a ventpipe leading from the float chamber.

In testimony whereof I affix my signature.

DONALD FORFAR.

